Starting from the bottom to meet existing siding above is always a bit tricky. If you don't get the overlap right (There needs to be expansion room between the top edge and the bottom rabbet of each piece) you run out of room to mesh the new and existing stuff at the top. I took a LOT of measurements to make sure I was going to be able to get that last gap correct. The last two pieces on the top took probably 45 mins alone. That beam is not plumb and the angle is not 45 degrees, so it took a bit of trim and check, trim and check to get them to fit properly.